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How Good Are We? Just Ask the V-Belt

by George Mahoney

“I really don’t understand what we are doing here. We are maintenance people; when something breaks, we fix it. You management guys are really making this a lot harder than it needs to be.”

These are the words spoken by one of our lead mechanics during a Kaizen event for defect elimination. As each word comes out of his mouth, I feel more and more crushed. Not only have I failed at making it clear why we want to eliminate defects, I also utterly confused everyone involved in the process.

After some soul-searching, I determined that the only way I can bring this message home is to use a tangible example to which they can relate. Instead of talking about process maps, standard operating procedures, and key performance indicators, I decide to talk about something they touch every day - v-belts.

To keep it as simple as possible, I decided to talk about how we would treat a v-belt in each step of the defect elimination journey. In the process, I linked each step of the journey to the stable domains identified by Winston Ledet. Winston is a key mentor of mine who first introduced me to the concept of defect elimination in his book, Don’t Just Fix It, Improve It!

Each of the five domains is listed in Figure 1.

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Figure 1: Domains of Operation

Challenge to the reader: As you read the remainder of this article, determine which domain currently applies to your plant. If I am successful at not “making it harder than it needs to be,” it should be as easy as looking at how you handle v-belts.

REGRESSIVE DOMAIN: DON’T FIX IT

In the regressive domain, no one really cares about the v-belt. Things are allowed to deteriorate, regardless of the impact to the business.

You know you are in the regressive domain if you hear something like this:

Site Manager: “Who cares if the people in Building 32B have no air conditioning because a v-belt ripped in half. We need to save money and we need to save it now. Fixing this is not in my budget.”

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V-Belt broken in half

REACTIVE DOMAIN: FIX IT AFTER IT BREAKS

In the reactive domain, we only care about the v-belt after it breaks. We don’t monitor it on a routine basis to keep track of its condition, nor do we make any effort to ensure it is installed properly in the first place. Nevertheless, when the belt does break, we all run around like maniacs trying to get a new one installed.

You know you are in the reactive domain if you hear something like this:

Site Manager: “Johnson, the people in Building 32B are sweating. Make sure we get a new v-belt installed immediately. Work as much overtime as you need, just make sure this gets done before they get back to work tomorrow.”

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175ºF V-Belt

It’s a good thing for Johnson he has an unlimited overtime budget and an army of mechanics just sitting around waiting for things to break. (Insert sarcastic tone here.) It’s also a good thing for Johnson that he has a stash of belts hidden in his shop. Who could blame him? No one ever really knows when something is going to break in this plant and even less than no one really trusts the store to have what you need when you need it.

(Side Note: It would be interesting to see how Johnson has the spare belts stored in his shop. What are the odds the new belt they installed is already defective?)

Site Manager (the next morning): “Johnson, great job getting that v-belt installed and the air conditioning back in operation last night. You saved the day. Here is a $25 gift card for you and a voucher for a pizza party for the boys in the shop. Keep up the great work.”

PLANNED DOMAIN: FIX IT BEFORE IT BREAKS

In the planned domain, we really care about when the belt is going to break and how efficiently we utilize our resources to replace it before it actually does.

Why do I say we care about when it is going to break? Because we pay PdM technicians to monitor the belt condition with infrared and vibration analysis on a three month frequency. At the first sign of belt wear, we instruct these same PdM technicians to create a work request to have the belt replaced before it has a chance to significantly impact equipment functionality.

Why do I say we care about how efficiently we utilize our resources? Because we pay a planner to develop a job plan and obtain the new v-belt a few weeks prior to the installation. We also pay a scheduler to coordinate a system shutdown with mechanic availability. The better we plan and schedule the work, the more efficiently our resources can execute the repair and the less time the equipment will have to be offline.

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Mounting bolts for motor

In the planned domain, you will most likely hear something like this:

Site Manager: “Reducing unexpected v-belt breakdowns is the best way for us to improve our schedule adherence metrics. These items should be on the schedule and executed before the equipment is negatively impacted.”

I am sure some of you reading this right now are feeling that the planned domain is a nice place to be. Who wouldn’t be in favor of reducing maintenance costs and increasing equipment uptime?

From a distance, this sounds both simple and terrific. But if it is so simple, why is it so hard to live in the planned domain?

It’s probably because we never did anything to address the source of the defect. Sure, we knew when the belt was going to break and determined the most cost-effective way to replace it, but we never addressed why it began to wear in the first place.

Enter the precision domain.

PRECISION DOMAIN: DON’T JUST FIX IT, IMPROVE IT

In the precision domain, we care about WHY the belt is breaking and begin to take efforts to eliminate the source of the defect so it does not happen again. We don’t just want to fix things, we want to improve them. (In case this is not abundantly clear, this mantra comes directly from Ledet’s book.)

In the precision domain, you will most likely hear something like this:

Mechanic: “I am tired of changing these v-belts every six months. We need to figure out why they are breaking so I don’t have to keep climbing into this air handler.”

(Side Note: Notice it is the mechanic and not the site manager speaking. The only way to truly eliminate defects is to empower the workforce to take action on the things impacting their day-to-day lives.)

In this domain, we take a close look at the predictive maintenance reports to determine if there are signs of misalignment or improper belt tensioning. We form a cross-functional team of engineers, mechanics and operators to inspect the wear patterns on the belt and the sheave’s condition.

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Neglected air handling unit

The investigation may indicate that the sources of the defect were a combination of both workmanship and design. As an example, let’s assume the belt was not tensioned properly because the mechanics had to pry the belts on the sheave. Let’s also assume the mechanics had to pry the belt on the sheave because there was no space for them to loosen the mounting bolts on the motor so it could be moved closer to the fan.

With the WHY identified, the team can now take action to Eliminate the source of the defect. They can work together to redesign the air handler’s housing to enable access to the mounting bolts on the motor. If they want to take it a step further, they can place a label on the housing indicating the correct belt tension and provide the mechanics with a tension tester to ensure the belt is tensioned properly.

WORLD-CLASS DOMAIN: DEFECT ELIMINATION AS A HABIT

In the world-class domain, we care about preventing defects from ever being added to our belt in the first place.

Every time a mechanic installs a v-belt, it is done perfectly. The mechanic does it so many times that it actually becomes a habit. This same type of habit extends to the engineers, who now ensure every air handler they design provides access to the mounting bolts on the motors. This culture of defect-free habits quickly extends around the plant.

After you have been on a few cross-functional action teams, you no longer want to be the one responsible for adding a new defect into the system.

WRAP UP

After having read this article, you should be able to easily determine in which domain your plant resides. Now that you have this information, what are you going to do with it?

I recommend you share this article with your maintenance team within the next week and develop a game plan to start eliminating defects. The more defects you eliminate, the less you have to chase them around all day.

Don’t Just Fix It, Improve It! www.mro-zone.com


part2George Mahoney currently acts as a Mentor, Sponsor and Instructor for Lean Six Sigma. He has worked in almost every facet of maintenance and engineering over the past 10 years. He served as an HVAC technician, a Design Engineer, a Maintenance Planner, a Maintenance Scheduler, a CMMS administrator and a Reliability Engineer. George is a certified Six Sigma Black Belt, who has made lean methodologies, root cause analysis and continuous improvement a part of his everyday life. George has a B.S. in Chemical Engineering from Columbia’s School of Engineering and Applied Science and a B.A. in Mathematics from Columbia College.

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